Siemens | S7-400PLC | PLC Simulation for S7-300 and S7-400

Preface, Contents
SIMATIC
PLC Simulation
for S7-300 and S7-400
Installing the PLC
Simulation Software
1
Getting Started with
S7-PLCSIM
2
Running a Program on the
Simulated PLC
3
Monitoring and Modifying
Data with the View Objects
4
Appendix
Troubleshooting
A
S7 Reference Information
B
Manual
Index
C79000-G7076-C201-01
Edition 1
Safety Guidelines
!
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well as to protect the product and connected equipment. These notices are highlighted in the
manual by a warning triangle and are marked as follows according to the level of danger:
Danger
indicates that death, severe personal injury or substantial property damage will result if proper
precautions are not taken.
Warning
indicates that death, severe personal injury or substantial property damage can result if proper
precautions are not taken.
Caution
indicates that minor personal injury or property damage can result if proper precautions are not taken.
Note
draws your attention to particularly important information on the product, handling the product, or
to a particular part of the documentation.
Qualified Personnel
The device/system may only be set up and operated in conjunction with this manual.
Only qualified personnel should be allowed to install and work on this equipment. Qualified
persons are defined as persons who are authorized to commission, to ground, and to tag circuits,
equipment, and systems in accordance with established safety practices and standards.
Correct Usage
!
Note the following:
Warning
This device and its components may only be used for the applications described in the catalog or the
technical description, and only in connection with devices or components from other manufacturers
which have been approved or recommended by Siemens.
This product can only function correctly and safely if it is transported, stored, set up, and installed
correctly, and operated and maintained as recommended.
Trademarks
SIMATIC and SINEC are registered trademarks of SIEMENS AG.
Some of the other designations used in these documents are also registered trademarks; the
owners’ rights may be violated if they are used by third parties for their own purposes.
Copyright Siemens AG 1997 All rights reserved
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data in this manual are reviewed regularly and any necessary corrections included in subsequent editions. Suggestions for improvement are welcomed.
Siemens AG
Automation Group
Industrial Automation Systems
P.O. Box 4848, D-90327 Nuremberg
Technical data subject to change.
Siemens AG 1997
Siemens Aktiengesellschaft
6ES7841-0AA0-BA0-01
Preface
Purpose
S7-PLCSIM is an optional software product for STEP 7 version 3.1. The
S7-PLCSIM software enables you to run and test your program on a
simulated programmable logic controller (PLC) that exists on your computer
or programming device (such as a PG 740). Because the simulation exists
completely within the STEP 7 software, you do not need to be connected to
any S7 hardware (CPU or I/O modules). With the simulated S7 CPU, you can
test and debug programs for both the S7-300 and S7-400 CPUs.
S7-PLCSIM provides a simple interface for monitoring and modifying
different parameters used by the program (such as for turning inputs on and
off). You can also use the various applications of the STEP 7 software while
you are running your program on the simulated CPU. This allows you to use
such tools as the variable table (VAT) to monitor and modify variables.
Audience
This manual is intended for engineers, programmers, and maintenance
personnel who have a general knowledge of programmable logic controllers.
Scope of the
Manual
This manual describes the features and the operation of S7-PLCSIM version
3.0. In order to install S7-PLCSIM, you must have an authorized version of
STEP 7 version 3.1 installed on your computer.
Other Manuals
You can find information in the online help for STEP 7 and for S7-PLCSIM.
In addition, the following manuals provide information about STEP 7.
Title
Content
System Software for
S7-300 and S7-400
Program Design
Programming Manual
The System Software for S7-300/S7-400 Program Design
Programming Manual provides basic information on the
structure of the operating system and of a user program of
an S7 CPU.
S7-300 and S7-400
System and Standard
Functions Reference
Manual
The S7 CPUs have integrated system functions and
organization blocks included with their operating system,
which you can use when programming. This manual
provides you with descriptions of the system functions,
organization blocks, and loadable standard functions
available in S7.
STEP 7 User Manual
The STEP 7 User Manual explains the main usage and the
functions of the STEP 7 automation software. This manual
provides you with an overview of the procedures used to
configure, program, and start up an S7-300/S7-400 PLC.
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
iii
Preface
Title
Statement List, Ladder
Logic, S7GRAPH 1,
SCL 1, and FBD 1
Manuals
1
Additional
Assistance
iv
Content
The manuals for the programming language packages
Statement List, Ladder Logic, and SCL (Structured Control
Language) contain both the user’s guide and the reference
description of the programming language or representation
type.
Optional package for system software for S7-300/S7-400
If you have any questions not answered in this or one of the other STEP 7
manuals, if you need information on ordering additional documentation or
equipment, or if you need information on training, please contact your
Siemens distributor or sales office.
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Contents
1
2
3
Installing the PLC Simulation Software
1.1
Product Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
PLC Features Supported . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Limitations of the Simulated PLC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Differences between a Simulated PLC and a Real PLC . . . . . . . . . . . . . . .
1-2
1-2
1-2
1-3
1-3
1-3
1.2
Authorization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-4
1.3
Installing and Uninstalling the S7-PLCSIM Software . . . . . . . . . . . . . . . . . .
1-6
Getting Started with S7-PLCSIM
2.1
Downloading the Sample Program to the Simulated PLC . . . . . . . . . . . . . .
Selecting and Downloading the Program . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-2
2-2
2.2
Setting Up the Simulated PLC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Creating View Objects for the Sample Program . . . . . . . . . . . . . . . . . . . . . .
2-3
2-3
2.3
Running the Sample Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Selecting the Execution Option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Starting the Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Saving the Layout of View Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-4
2-4
2-4
2-5
2.4
Using STEP 7 Tools to Monitor the Program . . . . . . . . . . . . . . . . . . . . . . . . .
Using a Variable Table to Monitor or Modify Data . . . . . . . . . . . . . . . . . . . . .
Using the Program Editor to Monitor Status . . . . . . . . . . . . . . . . . . . . . . . . . .
2-6
2-6
2-7
Running a Program on the Simulated PLC
3.1
Starting the PLC Simulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Selecting Simulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-2
3-2
3.2
Downloading a Program to the Simulated PLC . . . . . . . . . . . . . . . . . . . . . . .
3-3
3.3
Selecting Simulation Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Selecting Execution Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Using the Pause Function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Cycling Power On and Off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-4
3-4
3-4
3-4
3.4
Accessing Data in the Simulated PLC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Using the S7-PLCSIM View Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Using the STEP 7 Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Using a Variable Table to Monitor or Modify Data . . . . . . . . . . . . . . . . . . . . .
3-5
3-5
3-5
3-6
3-6
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
v
Contents
3.5
4
Opening, Saving, and Closing the Simulated PLC . . . . . . . . . . . . . . . . . . . .
Opening a Simulated PLC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Saving the Configuration of a Simulated PLC . . . . . . . . . . . . . . . . . . . . . . . .
Saving the Layout of View Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Closing the Simulated PLC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-7
3-7
3-7
3-7
3-7
Monitoring and Modifying Data with the View Objects
4.1
Controlling the CPU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Using the CPU View Object . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Displaying the Status of the CPU . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Changing the CPU Operating Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Resetting the CPU Memory (MRES) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4-2
4-2
4-2
4-3
4-3
4.2
Monitoring and Modifying the Data Used by the Program . . . . . . . . . . . . . .
Accessing the Data Stored in the CPU Memory . . . . . . . . . . . . . . . . . . . . . .
Creating View Objects for Accessing Program Data . . . . . . . . . . . . . . . . . .
Using the View Objects to Modify Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4-4
4-4
4-5
4-5
4.3
Displaying the Symbolic Addresses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Selecting the Symbol Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Showing Symbol Names in View Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4-6
4-6
4-6
4.4
Accessing the Accumulators, Status Word, and Address Registers . . . . .
4-7
4.5
Monitoring the Block Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Displaying the Contents of the Block Registers . . . . . . . . . . . . . . . . . . . . . . .
4-8
4-8
4.6
Monitoring the Data in the CPU Stacks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Monitoring the Nesting Stack and the MCR Stack . . . . . . . . . . . . . . . . . . . .
4-9
4-9
A
Troubleshooting
B
S7 Reference Information
B.1
Memory Areas for the S7-300 and S7-400 CPUs . . . . . . . . . . . . . . . . . . . . .
B-2
B.2
S7-PLCSIM Notation for Entering Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
B-4
Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Index-1
vi
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Contents
Figures
2-1
2-2
2-3
2-4
2-5
2-6
2-7
2-8
3-1
3-2
3-3
3-4
3-5
4-1
4-2
4-3
4-4
4-5
4-6
B-1
Downloading the S7_ZEBRA Program to the Simulated PLC . . . . . . . . . .
View Objects for the S7_ZEBRA Sample Program . . . . . . . . . . . . . . . . . . . .
Selecting Continuous Scan Program Execution . . . . . . . . . . . . . . . . . . . . . .
Selecting RUN Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Turning on Input PI0.0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sample View Objects Showing Status in RUN Mode . . . . . . . . . . . . . . . . . .
Example of a STEP 7 Variable Table (VAT) . . . . . . . . . . . . . . . . . . . . . . . . . .
Monitoring Program Status in the Ladder View . . . . . . . . . . . . . . . . . . . . . . .
Selecting PLC Simulation with the SIMATIC Manager . . . . . . . . . . . . . . . . .
Options for Downloading a Program to the Simulated PLC . . . . . . . . . . . .
Toolbar Buttons for Program Execution Options . . . . . . . . . . . . . . . . . . . . . .
Toolbar Buttons for Creating View Objects . . . . . . . . . . . . . . . . . . . . . . . . . . .
Example of a STEP 7 Variable Table (VAT) . . . . . . . . . . . . . . . . . . . . . . . . . .
CPU View Object . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Variable View Objects . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Showing Symbol Names for Program Elements . . . . . . . . . . . . . . . . . . . . . .
Accumulators and Status Word View Object . . . . . . . . . . . . . . . . . . . . . . . . .
Block Registers View Object . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Stacks View Object . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Memory Areas for the S7-300 and S7-400 CPUs . . . . . . . . . . . . . . . . . . . . .
2-2
2-3
2-4
2-4
2-4
2-5
2-6
2-7
3-2
3-3
3-4
3-5
3-6
4-2
4-5
4-6
4-7
4-8
4-9
B-2
Memory Areas for the S7-300 and S7-400 CPUs . . . . . . . . . . . . . . . . . . . . .
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Memory Areas for the S7-300 and S7-400 CPUs . . . . . . . . . . . . . . . . . . . . .
Data Formats for the “Variables” View Object . . . . . . . . . . . . . . . . . . . . . . . .
4-4
A-1
B-3
B-4
Tables
4-1
A-1
B-1
B-2
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
vii
Contents
viii
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Installing the PLC Simulation Software
1
Overview
The Setup program guides you through the installation of the S7-PLCSIM
software by means of dialogs and menus. You call the Setup program using
the standard Windows 95 software installation procedure.
System
Requirements
To install the S7-PLCSIM software, you require the following:
A programming device or PC with the STEP 7 (Release 3.1 or greater)
Standard package already installed, and with the following capabilities:
– 80486 processor (or higher)
– 16 Mbytes RAM
A VGA monitor, keyboard, and mouse which are supported by Microsoft
Windows 95
A hard drive with a memory capacity of 5 Mbytes for the S7-PLCSIM
optional package
At least 1 Mbyte free memory capacity on drive C for the Setup program
(Setup files are deleted when the installation is complete.)
Windows 95 operating system
Chapter
Overview
Section
Description
Page
1.1
Product Overview
1-2
1.2
Authorization
1-4
1.3
Installing and Uninstalling the S7-PLCSIM Software
1-6
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
1-1
Installing the PLC Simulation Software
1.1
Product Overview
Description
The S7-PLCSIM software enables you to run and test your program on a
simulated PLC that exists on your computer or programming device (such as
a PG 740). Because the simulation exists completely within the STEP 7
software, you do not need to be connected to any S7 hardware (CPU or I/O
modules). With the simulated S7 CPU, you can test and debug programs for
both the S7-300 and S7-400 CPUs.
S7-PLCSIM provides a simple interface for monitoring and modifying
different parameters used by the program (such as for turning inputs on and
off). You can also use the various applications of the STEP 7 software while
you are running your program on the simulated CPU. This allows you to use
such tools as the variable table (VAT) to monitor and modify variables.
Features
S7-PLCSIM offers the following features for running a program on a
simulated PLC:
A button on the SIMATIC Manager toolbar turns the routing to simulation
on or off. With the simulation button turned on, any new connection goes
automatically to the simulated PLC. When the simulation button is turned
off, any new connection goes to the real PLC.
The simulated PLC runs programs intended for either the S7-300 or
S7-400 CPU.
You can create “view objects” that allow you to access the input and
output memory areas, accumulators, and registers of the simulated CPU.
You can modify any of this data.
You can choose to have the timers run automatically, or you can set or
reset the timers manually.
You can change the CPU operating mode (STOP, RUN, and RUN-P) as
with a real CPU. In addition, S7-PLCSIM provides a Pause function that
allows you to halt the CPU momentarily without affecting the state of the
program.
S7-PLCSIM also allows you to use all of the STEP 7 tools to monitor and
modify the activities of the simulated PLC.
1-2
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Installing the PLC Simulation Software
PLC Features
Supported
The simulated PLC functions as either an S7-300 or S7-400 CPU. It provides
the following capabilities:
Timers: 512 (T 0 to T 511). Timers use a “virtual” clock rather than a
real-time clock. Each timer instruction decrements using a simulation
clock which is based on the instructions executed in the program. Timers
can run faster or slower than real time depending on the size of the
program and the computer hardware used to run the simulation.
Although the timers do not run in real time, they will time out
consistently relative to program execution (even if you use single-scan
program execution or single-step debugging).
Memory bits: up to 16,384 bits (2048 bytes) of M memory
I/O memory: up to 16,384 bits (2048 bytes) of I/O memory
Logic blocks and data blocks: 2048 function blocks (FBs) and functions
(FCs), and 2048 data blocks (DBs)
System functions (SFCs): SFC20, SFC21, SFC22, SFC23, SFC26, SFC27,
SFC46, SFC52, and SFC64
For SFC26 and SFC27, the only input parameter supported is 0.
OBs: OB1 (main program cycle), OB100 (complete restart), and OB101
(restart)
Limitations of the
Simulated PLC
S7-PLCSIM has the following limitations:
You can run only one simulated PLC at a time.
The simulated PLC does not support all of the error messages written to
the diagnostic buffer. It supports only the information available from the
RUN mode transitions. It also supports diagnostics of fatal errors and
time-out events, such as infinite loops.
System data blocks (SDBs) are downloaded with your program, but are
ignored by the simulated PLC.
Differences
between a
Simulated PLC
and a Real PLC
The simulated PLC provides the following capabilities which are not
available in a real PLC:
The Pause function halts the simulated CPU and allows you to resume the
execution of the program at the instruction where the program was halted.
Any change that you make with a view object immediately updates the
contents of the memory location. The CPU does not wait until the
beginning or the end of the scan to update any changed data.
Execution options allow you to select how the CPU runs the program:
– Single Scan executes the program for one scan and then waits for you
to start the next scan.
– Continuous Scan executes the program like a real PLC: it starts a new
scan immediately after the previous one finishes.
Using STOP mode does not change the state of the outputs (PQ).
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
1-3
Installing the PLC Simulation Software
1.2
Authorization
Overview
The S7-PLCSIM programming software requires a product-specific
authorization (or license for use). The software is therefore copy-protected
and can be used only if the relevant authorization for the program or software
package has been found on the hard disk of the respective programming
device or PC.
Authorization Disk
A read-only authorization disk is included with the software. It contains the
authorization and the program required to display, install, and remove the
authorization called AUTHORS.
For more information and rules on how to handle authorizations, see the
STEP 7 User Manual.
!
Installing the
Authorization for
the First Time
Caution
Note the information in the README.TXT file on the authorization disk. If
you do not adhere to these guidelines, the authorization may be irretrievably
lost.
When installing your software for the first time, a message prompts you to
install the authorization. Follow the steps outlined below:
1. When prompted, insert the authorization disk in a drive.
2. Acknowledge the prompt.
The authorization is transferred to a physical drive and your computer
registers the fact that the authorization has been installed.
1-4
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Installing the PLC Simulation Software
Adding an
Authorization at a
Later Date
If you attempt to start the S7-PLCSIM software and there is no authorization
available for the software, a message informs you of this. If you want to
install the authorization, use the AUTHORS program on the authorization
disk. This program allows you to display, install, and remove authorizations.
The program is menu-driven.
Note
Always enter drive C as the destination drive for the authorization for
S7-PLCSIM.
Removing an
Authorization
If you should need to repeat the authorization, for example, if you want to
reformat the drive on which the authorization is located, you must remove
the authorization first. You need the original authorization disk to do this.
To transfer the authorization back to the authorization disk, follow the steps
outlined below:
1. Insert the original authorization disk in your floppy disk drive.
2. Start the program AUTHORS.EXE from the authorization disk.
3. Select the menu command Authorization Remove.
4. In the dialog box, enter the drive on which the authorization is located
and confirm the dialog box. A list of all authorizations on the respective
drive is displayed.
5. Select the authorization you want to remove and confirm the dialog box.
If the process is completed without error, the following message appears:
”Authorization <Name> successfully removed from drive <X:>.”
6. Acknowledge the message.
The dialog box with the list of authorizations remaining on the drive is
then displayed. Close the dialog box if you do not want to remove any
more authorizations.
You can then use the disk again to install an authorization.
If Your Hard Drive
is Defective...
If a fault occurs on your hard disk before you can back up the authorization,
contact your local Siemens representative.
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
1-5
Installing the PLC Simulation Software
1.3
Installing and Uninstalling the S7-PLCSIM Software
Overview
S7-PLCSIM includes a Setup program which executes the installation
automatically. Prompts on the screen guide you step by step through the
installation procedure.
Preparing for
Installation
Before you can start installing the software, Windows 95 must be started and
the STEP 7 basic package loaded.
’
Starting
the
Installation
Program
The Setup program guides you step by step through the installation process.
You can switch to the next step or to the previous step from any position. To
start the installation program, proceed as follows:
1. Start the dialog box for installing software under Windows 95 by
double-clicking on the Add/Remove Programs icon in the Control Panel.
2. Click on “Install...”
3. Insert disk 1 and click on “Next.” Windows 95 searches automatically for
the installation program SETUP.EXE.
4. Follow the instructions displayed by the installation program step by step.
If a Version of
S7-PLCSIM is
Already Installed
If the installation program finds another version of S7-PLCSIM on the
programming device, the program reports this and prompts you to decide
how to proceed by offering the following choices:
Abort the installation so that you can uninstall the old S7-PLCSIM
version under Windows 95 and then start the installation again.
Continue the installation and overwrite the old version with the new
version.
Your software is better organized if you uninstall any older versions before
installing the new version. Overwriting an old version with a new version has
the disadvantage that if you then uninstall, any remaining components of the
old version are not removed.
During installation, queries are shown in dialog boxes for you to answer, and
options are displayed for you to select. Read the following notes so you can
reply to the queries faster and more easily.
Uninstalling
Use the usual Windows 95 procedure to uninstall:
1. Start the dialog box for installing software under Windows 95 by
double-clicking on the Add/Remove Programs icon in the Control Panel.
2. Select the SIMATIC S7-PLCSIM entry in the displayed list of installed
software. Click on the “Add/Remove...” button to uninstall the software.
3. If the “Remove Enable File” dialog boxes appear, click the “No” button if
you are unsure how to respond.
1-6
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Installing the PLC Simulation Software
Using the Scope of
Installation
All languages of the user interface and all examples require approximately
5 Mbytes of memory capacity.
Using
Authorization
During installation, the program checks to see whether an authorization is
installed on the hard disk. If no authorization is found, a message appears
that the software can be used only with an authorization. If you wish, you can
run the authorization program immediately or continue the installation and
execute the authorization at a later date.
In the first case, insert the authorization disk when you are prompted to do
so. (See Section 1.2.)
Result of the
Installation
Once the installation has been completed successfully, a message to that
effect is displayed on the screen.
If Errors Occur
during the
Installation
The following errors may cause the installation to fail:
Initialization error immediately after starting Setup: The SETUP.EXE
program was probably not started under Windows 95.
Not enough memory: You need at least 5 Mbytes of free space on your
hard disk.
Bad disk: Verify that the disk is bad, then call your local Siemens
representative.
Operator error: Start the installation again and read the instructions
carefully.
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
1-7
Installing the PLC Simulation Software
1-8
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Getting Started with S7-PLCSIM
Overview
2
STEP 7 provides a sample program called “S7_ZEBRA”. You can use this
program to become familiar with the features of the S7-PLCSIM software.
This chapter provides the basic steps for downloading and running the
program on a simulated CPU. It also provides information about using the
different view objects and a variable table (VAT) with the simulation.
Chapter
Overview
Section
Description
Page
2.1
Downloading the Sample Program to the Simulated PLC
2-2
2.2
Setting Up the Simulated PLC
2-3
2.3
Running the Sample Program
2-4
2.4
Using STEP 7 Tools to Monitor the Program
2-6
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
2-1
Getting Started with S7-PLCSIM
2.1
Downloading the Sample Program to the Simulated PLC
Selecting and
Downloading the
Program
STEP 7 provides a sample program that you can download to the simulated
PLC. Use the following procedure to download the sample program:
1. Start the SIMATIC Manager.
2. Turn on the routing to the simulator by clicking on the Simulation On/Off
button located on the SIMATIC Manager toolbar, as shown in Figure 2-1,
or by selecting the menu command Options Simulate Modules.
3. Use the SIMATIC Manager menu command File Open Project to
open the S7_ZEBRA project. This project is supplied with the STEP 7
software.
4. Navigate through the object hierarchy until you get to the blocks object.
Figure 2-1 shows the S7_ZEBRA project structure.
5. Select the menu command PLC Download or click on the download
button to download the blocks object to the simulated CPU.
(Downloading the blocks automatically creates the simulated CPU.)
The S7-PLCSIM application window opens with a default CPU view object.
The Windows taskbar displays an icon to alert you that there is a simulated
PLC. (If you place the mouse cursor on the icon, a tool tip displays the MPI
number.)
✂
SIMATIC Manager - S7_ZEBRA
File Edit Insert PLC View Options Window Help
S7_ZEBRA - <Standard Hierarchy, Offline> (Project)
SIMATIC 300-Station(1)
S7_ZEBRA
SIMATIC 300-Station(1)
MPI-Netz(1)
CPU314(1)
S7-Program(1)
Download button
Source Files
Blocks
Simulation On/Off button
ZEBRA blocks object
Press F1 for Help
Figure 2-1
2-2
NUM
Downloading the S7_ZEBRA Program to the Simulated PLC
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Getting Started with S7-PLCSIM
2.2
Setting Up the Simulated PLC
Creating View
Objects for the
Sample Program
The S7_ZEBRA sample program uses several inputs, outputs and timers. You
can use a view object to turn the inputs on and off, and you can watch the
timer values and outputs change as the program runs. Figure 2-2 shows the
view objects used with the sample program. Use the following procedure to
create the different view objects:
1. Create a view object that accesses the inputs used by the program:
– Select the menu command Insert Input Variable.
– The default value is PIB0 (for peripheral input byte 0). Press ENTER
to accept.
2. Create a view object that accesses the outputs used by the program:
– Select the menu command Insert Output Variable.
– The default value is PQB0 (for peripheral output byte 0). Press ENTER
to accept.
3. Create three view objects to access the timers used by the program:
– Select the menu command Insert Timer.
– The default value is T 0, with the 0 highlighted. Type 2 in the view
object (for Timer T 2) and press ENTER.
– Repeat for timers T 3 and T 4.
PLC Simulation – Zebra.plc
PLC
Execute
View
Options Window Help
✂
Simulation Edit Insert
PIB
CPU 300/400
SF
DC
RUN
STOP
T
T
RUN-P
PIB
RUN
STOP
7
0
6
Bits
5
4
3
T
2
0
PQB
0
7
5
T
T=0
3
6
T
3
T
0 sec
Bits
4
3
2 1
0
T=0
4
4
0 ms
T=0
NUM
Ready
Figure 2-2
2 1
0
MRES
2
0 ms
PQB
0
View Objects for the S7_ZEBRA Sample Program
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
2-3
Getting Started with S7-PLCSIM
2.3
Running the Sample Program
Selecting the
Execution Option
With the sample program downloaded to the CPU, you can now run the
program. Before starting the program, ensure that the program execution is
set for continuous scan. Use the menu command Execute Mode Continuous Scan or click on the toolbar button (shown in Figure 2-3) to
select the execution control option for running the program continuously.
Click here for Continuous Scan program execution.
Figure 2-3
Starting the
Program
Selecting Continuous Scan Program Execution
Use the following procedure to switch the CPU into RUN mode and to start
the program.
1. Click the RUN check box in the CPU view object. See Figure 2-4.
CPU 300/400
SF
DC
RUN
STOP
Figure 2-4
RUN-P
Click here to switch
CPU to RUN mode.
RUN
STOP
MRES
Selecting RUN Mode
2. Click either bit 0 or bit 1 in the Input Variable view object to turn on
PI0.0 or PI0.1, as shown in Figure 2-5.
PIB
PIB
7
Figure 2-5
2-4
0
0
6
Bits
5
4
3
2 1
0
Click here to turn on
input bit PI0.0.
Turning on Input PI0.0
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Getting Started with S7-PLCSIM
In the view objects, you can watch the timer values as they change and the
outputs as they turn on or off, as shown in Figure 2-6. As each timer reaches
its preset value, the corresponding outputs turn on or off.
To speed up the operation of the sample program, you can reset the timers in
turn by clicking on the “T = 0” button in the Timer view objects.
Saving the Layout
of View Objects
You can save your layout of view objects within the simulated PLC window
by selecting the menu command Simulation Layout Save.... You can then
retrieve the saved layout at any time by selecting the menu command
Simulation Layout Open...
PLC Simulation – Zebra.plc
PLC
Execute
View
Options Window Help
✂
Simulation Edit Insert
PIB
CPU 300/400
SF
DC
RUN
STOP
T
T
RUN-P
PIB
RUN
STOP
7
0
6
Bits
5
4
3
2 1
T
2
PQB
0
7
5
T
T=0
3
6
T
3
T
0.0 sec
Ready
Figure 2-6
0
0
Bits
4
3
2 1
0
MRES
2
2840 ms
PQB
0
T=0
4
4
0 ms
T=0
NUM
Sample View Objects Showing Status in RUN Mode
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
2-5
Getting Started with S7-PLCSIM
2.4
Using STEP 7 Tools to Monitor the Program
Using a Variable
Table to Monitor or
Modify Data
STEP 7 allows you to use a variable table (VAT) to monitor the status of any
variable in your program. Figure 2-7 shows a VAT for the sample program.
You can also modify the variables which are defined for the VAT. To monitor
program status using the variable table, follow these steps:
1. Access the SIMATIC Manager window.
2. Select VAT1 and double-click with the mouse or use the menu command
Edit Open Object to open the variable table for the “S7_ZEBRA”
project.
3. Select the menu command PLC Connect To Configured PLC to
establish an online connection with the program in the simulated PLC.
You can now observe the values of the input, output, and timer elements in
the Monitor Value column of the VAT, as shown in Figure 2-7.
S7_ZEBRA\SIMATIC 300–Station1\CPU314(1)\S7–Program(1)\...\VAT1
Address
Monitor Format
Monitor Value
Modify Value
Q
0.1
“Ped_green”
BIN
2#0
–––
Q
0.5
“Car_red”
BIN
2#0
–––
Q
0.6
“Car_orange”
BIN
2#1
–––
Q
0.7
“Car_green”
BIN
2#0
–––
T
4
“Car_delay_red”
SIMATIC_TIME
S5T#4s820ms S5T#0ms
T
5
“Car_red_orange_phase” SIMATIC_TIME
S5T#0ms
S5T#0ms
T
6
“Ped_delay_green”
SIMATIC_TIME
S5T#0ms
S5T#0ms
I
0.0
“Switch_right”
BIN
2#1
2#1
I
0.1
“Switch_left”
BIN
2#0
2#1
Figure 2-7
2-6
Symbol
Example of a STEP 7 Variable Table (VAT)
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Getting Started with S7-PLCSIM
Using the Program
Editor to Monitor
Status
To view the execution of program logic in the ladder view of the program,
follow these steps:
1. Access the SIMATIC Manager window.
2. Select FC1 in the online view and double-click with the mouse or use the
menu command Edit Open Object to open the program for the
“S7_ZEBRA” project.
If necessary, select View LAD in the LAD/STL/FBD application to
switch from the statement list view to the ladder view.
3. Select the menu command Debug Monitor to enable the animation of
program execution in the ladder networks.
You can now observe the power flow to the inputs, outputs, memory bits, and
timer elements in the ladder networks, as shown in Figure 2-8.
LAD/STL/FDB – [S7_ZEBRA\SIMATIC 300–STATION(1)\CPU 314(1)\...\ - [FC1 - <On-line>]
Network 1 : Determining green request for pedestrians
Determining whether I 0.0 or I 0.1 is set
I0.0
T6
T5
M0.0
I0.1
M0.0
Network 2 : Green phase for cars
If I 0.0 or I 0.1 are not set, the light stays green for cars.
M0.0
Figure 2-8
Q0.7
Monitoring Program Status in the Ladder View
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
2-7
Getting Started with S7-PLCSIM
2-8
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Running a Program on the Simulated PLC
Overview
Chapter
Overview
3
S7-PLCSIM works with the STEP 7 software to test and debug your program
on a simulated PLC. This chapter describes how to start the PLC simulation,
download a program, select execution options, and access data in the
program.
Section
Description
Page
3.1
Starting the PLC Simulation
3-2
3.2
Downloading a Program to the Simulated PLC
3-3
3.3
Selecting the Simulator Options
3-4
3.4
Accessing Data in the Simulated PLC
3-5
3.5
Opening, Saving, and Closing the Simulated PLC
3-7
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
3-1
Running a Program on the Simulated PLC
3.1
Starting the PLC Simulation
You use the SIMATIC Manager to determine whether a program that you
download will go to a real PLC or to a simulated PLC.
Selecting
Simulation
STEP 7 provides a button on the SIMATIC Manager toolbar that turns the
routing to S7-PLCSIM on or off. With the simulation button turned on, any
new request for an online CPU connection is re-routed to a simulated CPU.
Be aware, however, that selecting simulation does not close any online
connections that you may have with a real PLC. Because of the risk of
unintentionally editing a real online program, you cannot start a simulation
session until you close all windows or applications that are connected to real
PLCs.
Figure 3-1 shows the SIMATIC Manager window with the Simulation On/Off
button.
Note
You can have only one simulated PLC active at a time. When the Simulation
On/Off button is turned on, clicking on the Accessible Nodes button shows
the node address for the simulated CPU that you have created. When the
Simulation On/Off button is turned off, the Accessible Nodes window shows
the network of real PLCs.
✂
SIMATIC Manager - S7_ZEBRA
File Edit Insert PLC View Options Window Help
S7_ZEBRA - <Standard Hierarchy, Offline> (Project)
SIMATIC 300-Station(1)
S7_ZEBRA
SIMATIC 300-Station(1)
MPI-Net(1)
CPU314(1)
S7-Program(1)
Source Files
Simulation On/Off button
Blocks
Accessible Nodes button
Press F1 for Help
Figure 3-1
3-2
NUM
Selecting PLC Simulation with the SIMATIC Manager
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Running a Program on the Simulated PLC
3.2
Downloading a Program to the Simulated PLC
S7-PLCSIM starts when you download a program to the simulated PLC.
STEP 7 provides two options for downloading a program:
You can download an existing program with the SIMATIC Manager.
You can download your program from the program editor.
After you download your program, an icon appears in the Windows taskbar to
inform you that there is an active connection to the simulated PLC.
For more information about downloading programs, refer to the STEP 7 User
Manual.
SIMATIC Manager
Program Editor
SIMATIC Manager - S7_ZEBRA
Edit
Insert
PLC
View
Options
Window
Help
Network 1 :
✂
File
S7_ZEBRA - <Offline> (Project)
SIMATIC 300-Station(1)
S7_ZEBRA
SIMATIC 300-Station(1)
MPI-Netz(1)
CPU314(1)
S7-Program(1)
Source Files
Blocks
Network 2 :
Press F1 for Help
NUM
S7-PLCSIM
PLC Simulation – SimView1
CPU 300/400
SF
DC
RUN
STOP
Figure 3-2
RUN-P
RUN
STOP
MRES
Options for Downloading a Program to the Simulated PLC
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
3-3
Running a Program on the Simulated PLC
3.3
Selecting Simulation Options
Selecting
Execution Options
You select the program execution options with the Execute menu commands.
You can also access these options with the toolbar buttons, as shown in
Figure 3-3. These options control the execution of the program:
S Continuous Scan: The CPU executes one complete scan and then starts
another scan. Each scan consists of the CPU reading the peripheral inputs
(PI), executing the program, and then writing the results to the peripheral
outputs (PQ).
S Single Scan: The CPU executes one scan and then waits for you to initiate
another scan. Each scan consists of the CPU reading the peripheral inputs
(PI), executing the program, and then writing the results to the peripheral
outputs (PQ).
Using the Pause
Function
The Pause function allows you to halt the execution of a program
temporarily. Unlike placing the CPU into STOP mode (which restarts the
execution of the program at the first instruction in your program when you
return to RUN mode), halting the execution of a program lets you resume the
execution at the instruction where you halted the program.
You can turn the Pause function on and off with the Execute " Pause menu
command, or you can use the toolbar button, as shown in Figure 3-3.
Cycling Power
On and Off
You can simulate turning power on and off for the CPU. This allows you to
check the different startup OBs. Use the PLC " Power Off/Power On menu
commands to cycle power. (You must turn the power on before you change
the node address for the CPU.)
S7-PLCSIM
Toolbar
Next Scan
Single Scan
Pause
Continuous Scan
Figure 3-3
3-4
Toolbar Buttons for Program Execution Options
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Running a Program on the Simulated PLC
3.4
Accessing Data in the Simulated PLC
Overview
You can access data in the simulated PLC with the “view objects” provided
by the main S7-PLCSIM window, or with the standard STEP 7 tools for
monitoring program status, or a combination of both.
Using the
S7-PLCSIM
View Objects
View objects allow you to monitor the program by displaying the values or
the states of the variables used by the program. Some view objects are
read-only; others allow you to change the values of specific memory
locations. S7-PLCSIM provides view objects for the following types of data:
Variable data. This view object allows you to display or modify the values
of timers, counters, I/O bits, or other memory locations.
The following view objects can provide useful information for debugging a
program when used with the breakpoint function in STEP 7:
Accumulators and the status word. The read-only “ACCUs & Status
Word” view object accesses the contents of the accumulators and the
values stored in the pointer address registers (AR1 and AR2). It also
displays the states of the status word bits.
Block registers. The read-only “Block Regs” view object accesses the
contents of the data block address registers (DB1 and DB2). It also
displays the identity of the logic block being executed and the step
address counter (SAC).
Stacks (nesting stack and MCR stack). The read-only “Stacks” view
object accesses the contents of the nesting stack, which consists of the
RLO bit and the OR bit of the status word. (The nesting stack shows the
state of the status word for each instruction in the logic string.) This view
object also shows the state of the MCR (master control relay) stack.
There is no restriction on the number of view objects that you can create and
display. For more information on using view objects, see Chapter 4.
Create “Variable”
view object
Figure 3-4
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Create “Stacks”
view object
Create “ACCUs
& Status Word”
view object
Create “Block Regs”
view object
Toolbar Buttons for Creating View Objects
3-5
Running a Program on the Simulated PLC
Using the STEP 7
Tools
You can use the STEP 7 tools to monitor and modify the program that is
being executed by the simulated CPU. This allows you to create and test a
variable table (VAT) or to use the debugging tools provided by STEP 7. For
more information about the STEP 7 tools, see the STEP 7 User Manual or the
manual for your programming language.
Remember to disconnect any STEP 7 tool before closing the simulated CPU
or exiting the S7-PLCSIM application.
Note
Using the Pause function can cause the STEP 7 tools to disconnect from the
simulated PLC because of a time-out while STEP 7 waits for a request to be
acknowledged. After you turn Pause off, you can reconnect the STEP 7 tool.
Using a Variable
Table to Monitor or
Modify Data
You can use a variable table (VAT) to monitor the status of any variable in
your program. You can also modify the variables which are defined for the
VAT. You can use the simulated CPU to test a VAT that is being prepared as
an interface. Figure 3-5 shows a sample VAT for the S7_ZEBRA program.
S7_ZEBRA\SIMATIC 300–Station1\CPU314(1)\S7–Program(1)...\VAT1
Address
Monitor Format
Monitor Value
Modify Value
Q
0.1
“Ped_green”
BIN
–––
Q
0.5
“Car_red”
BIN
–––
Q
0.6
“Car_orange”
BIN
–––
Q
0.7
“Car_green”
BIN
–––
T
4
“Car_delay_red”
SIMATIC_TIME
S5T#0ms
T
5
“Car_red_orange_phase”
SIMATIC_TIME
S5T#0ms
T
6
“Ped_delay_green”
SIMATIC_TIME
S5T#0ms
I
0.0
“Switch_right”
BIN
2#1
I
0.1
“Switch_left”
BIN
2#1
Figure 3-5
3-6
Symbol
Example of a STEP 7 Variable Table (VAT)
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Running a Program on the Simulated PLC
3.5
Opening, Saving, and Closing the Simulated PLC
Opening a
Simulated PLC
You can open a simulated PLC in one of the following ways:
S With the Simulation On/Off button on, you can download a program from
the SIMATIC Manager or the program editor.
S If you have already saved one or more simulated PLCs to a file, you can
open a specific PLC by using the Simulation " Open menu command.
Note
S7-PLCSIM supports only one simulated PLC at a time.
Saving the
Configuration of a
Simulated PLC
Use the Simulation " Save or Simulation " Save As... menu command to
archive a simulated PLC. The following elements are saved with the PLC:
S Program
S CPU operating mode (RUN-P, RUN, or STOP)
S Power state (on or off)
S Execution control option (continuous scan or single scan)
S The status of the I/O (PI and PQ memory areas)
S Timer values
Saving the Layout
of View Objects
To save the layout of the view objects you have inserted for the simulated
PLC, select the menu command Simulation " Layout Save.... Any time you
reopen a saved simulated PLC, you can also open a saved layout using the
Simulation " Layout Open... menu command.
Closing the
Simulated PLC
You can close a PLC either by selecting the Simulation " Close menu
command or by clicking on the button in the top-right corner of the CPU
view object. Closing the simulated PLC ends the simulation of the program,
but does not exit the S7-PLCSIM application.
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
3-7
Running a Program on the Simulated PLC
3-8
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Monitoring and Modifying Data with the
View Objects
Overview
4
S7-PLCSIM provides view objects that allow you to display the following
information:
Variable data, such as timers, counters, inputs, and outputs
Accumulators and status word
Address registers
Nesting stack and MCR stack
Any change made by a view object affects the program immediately. When
you use a STEP 7 variable table to change a value, the CPU reads that
change at the beginning of the next scan.
Chapter
Overview
Section
Description
Page
4.1
Controlling the CPU
4-2
4.2
Monitoring and Modifying the Data Used by the
Program
4-4
4.3
Displaying the Symbolic Addresses
4-6
4.4
Accessing the Accumulators, Status Word, and Address
Registers
4-7
4.5
Monitoring the Block Registers
4-8
4.6
Monitoring the Data in the CPU Stacks
4-9
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
4-1
Monitoring and Modifying Data with the View Objects
4.1
Controlling the CPU
Using the CPU
View Object
After you download a program, the S7-PLCSIM application window displays
a CPU view object that has the same node address as the downloaded
program. Figure 4-1 shows a sample CPU view object. From this view object,
you can perform the following functions:
Change the CPU operating mode (STOP, RUN, and RUN-P)
Reset the CPU memory (MRES)
Displaying the
Status of the CPU
A real CPU provides LED indicators for displaying the status of the CPU.
The CPU view object also provides the following indicators that display the
CPU status:
SF (system fault) indicates an error condition.
DC (power supply) indicates that power to the CPU is on.
RUN indicates that the CPU is in RUN mode.
STOP indicates that the CPU is in STOP mode.
For more information about the S7-300 and S7-400 CPUs, refer to the System
Software for S7-300 and S7-400 Program Design Programming Manual or to
the online help for STEP 7.
CPU 300/400
SF
DC
RUN
STOP
CPU status
indicators
Figure 4-1
4-2
CPU operating
mode controls
RUN-P
RUN
STOP
MRES
CPU View Object
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Monitoring and Modifying Data with the View Objects
Changing the CPU
Operating Mode
The check boxes on the CPU view object allow you to change the CPU
operating modes:
S In STOP mode, the CPU is not executing the program. To download a
program that includes SDBs or to change the node address, you must
place the CPU in STOP mode. Unlike a real CPU, placing the CPU in
STOP mode does not change the state of the outputs (PQ).
S In RUN mode, the CPU executes the program. As with a real CPU, you
cannot download any new programs or logic blocks when the CPU is in
RUN mode. You can use the STEP 7 tools to monitor (but not to modify)
the variables.
S In RUN-P mode, the CPU executes the program. When the CPU is in
RUN-P mode, you can download new programs or logic blocks, and you
can modify the variables with the STEP 7 tools.
To change the CPU mode, click on the box for STOP, RUN, or RUN-P. The
CPU status indicators show whether the CPU is in RUN (or RUN-P) mode or
in STOP mode.
Resetting the CPU
Memory (MRES)
The CPU view object provides an MRES button for resetting the memory of
the CPU. When you reset the CPU memory, the simulated CPU performs the
following tasks:
S The memory areas are reset.
S The program blocks are deleted.
Use the following procedure to reset the CPU memory:
1. Place the CPU in STOP mode.
2. Click on the MRES button, or select the menu command
PLC " Clear/Reset.
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
4-3
Monitoring and Modifying Data with the View Objects
4.2
Monitoring and Modifying the Data Used by the Program
You can create view objects that access the data stored in the different
memory areas of the simulated CPU. S7-PLCSIM provides view objects that
contain default addresses for a timer, a counter, an input, and an output. You
can also create a generic view object to access the data stored in other
memory areas.
Accessing the
Data Stored in the
CPU Memory
The view objects that you create with the Insert menu commands allow you
not only to display the contents of the different memory areas within the
CPU, but also to modify those values and immediately see the effect on your
program. When you change a value in a data field, press ENTER for it to be
accepted.
You can use these view objects to access not only the inputs and outputs, but
also the timers, counters, and the data used by the program. Table 4-1 lists
the memory areas that can be accessed.
For more information about the memory areas, refer to the System Software
for S7-300 and S7-400 Program Design Programming Manual or to the
online help for STEP 7.
Note
The peripheral input (PI) memory area overwrites the input (I) memory area
at the beginning of every CPU scan. If you use the view object to modify a
value in the I memory area, that value is overwritten at the beginning of the
next scan. To enter an input value that will not be overwritten on every scan,
enter the value to the PI memory area.
Table 4-1
Memory Areas for the S7-300 and S7-400 CPUs
Memory Area
PI
peripheral (external) input
Description
The CPU writes the PI memory to the I memory at the beginning of each scan.
PQ peripheral (external) output The CPU writes the Q memory to the PQ memory at the end of every scan.
I
process-image input
The I memory area is overwritten by the PI memory area at the beginning of
every scan.
Q
process-image output
The Q memory area overwrites the PQ memory area at the end of each scan.
M
bit memory
The M memory area provides storage for interim results calculated in the
program.
T
timer
The T memory area provides the timers used by the program.
C
counter
The C memory area provides the counters used by the program.
DB data block
4-4
The DB memory address references the data stored in the data blocks for the
program.
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Monitoring and Modifying Data with the View Objects
Creating View
Objects for
Accessing
Program Data
To create view objects for monitoring and modifying the data used by the
program, use the Insert menu commands. Figure 4-2 shows several examples
of the view objects. Use the following procedure to access a memory address
with a view object:
1. Enter the memory address to be accessed and press ENTER. For example:
“PIB0” accesses byte 0 of the PI memory area and “T 2” accesses timer 2.
2. Use the drop-down list box to select the appropriate representation for the
data that will be displayed or entered (such as binary, decimal, or
hexadecimal).
PIB
PIB
7
0
T
0
6
T
Bits
5
4
3
2 1
2
2
0
0 ms
PIW
PIW
0
0
PIW
PIW
Decimal
8
8
Hex
0
Figure 4-2
Using the View
Objects to
Modify Data
T=0
0
Variable View Objects
Use the following guidelines to modify data in the view objects:
When you select bit format for a variable such as a peripheral input byte,
the eight check boxes correspond to bits 0 through 7. To activate any of
the bits in the view object, click on the corresponding check box to
change the state from off to on (0 to 1). A check mark appears, indicating
a state of 1 or on. Clear the check box to turn the bit off.
For variables that you specify as bytes, words, or double words, use the
drop-down list box to select the appropriate representation for the data
that you want to enter (such as binary, decimal, or hexadecimal). Enter
the value in the text field in the corresponding format and press ENTER.
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
4-5
Monitoring and Modifying Data with the View Objects
4.3
Displaying the Symbolic Addresses
Selecting the
Symbol Table
You can display the symbol names assigned to the absolute addresses in any
of the view objects of your simulated PLC. To establish a link to the symbol
table associated with the downloaded program, follow these steps:
1. Select the menu command Options Show Symbols...
2. Use the browser dialog box to select the symbol table associated with the
downloaded program.
3. Click on the “OK” button to confirm the selection.
Showing Symbol
Names in View
Objects
To show the symbol name associated with an element in your program,
follow these steps:
1. Select the view object of a variable that you want to display with its
symbol name.
2. With the cursor in the address field, click the right mouse button to open a
pop-up menu.
3. Select Show Symbol from the menu. (If there is no symbol name
associated with the variable, Show Symbol is unavailable.)
You can point to any address that has a symbol name associated with it and
see the full symbol name in a tool tip. For bits of a byte address, the only way
to see the symbol names is to display the tool tip for each bit check box.
Figure 4-3 shows examples of view objects with the symbol names displayed
in the address field. Note that the absolute address is still displayed in the
title bar of the view object.
Q
Click the right
mouse button.
Q
7
Undo
0.1
Cut
Bits
Copy
0.1
6
5
Paste
3 2 1
Delete
4
0
Select All
Select
Q
0.1
T
Ped_green
7
6
5
✓ Show Symbol
Bits
4
3
2 1
4
Car_delay_red
0
0 ms
Figure 4-3
4-6
T=0
Showing Symbol Names for Program Elements
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Monitoring and Modifying Data with the View Objects
4.4
Accessing the Accumulators, Status Word, and Address Registers
You can display the contents of the accumulators, the status word, and the
address registers in the CPU by opening the “ACCUs & Status Word” view
object. Select the menu command View Accumulators to open this view
object.
Figure 4-4 shows the “ACCUs & Status Word” view object.
For more information about the status word and the accumulators for the
S7-300 and S7-400 CPUs, refer to the System Software for S7-300 and
S7-400 Program Design Programming Manual or to the online help for
STEP 7.
ACCUs & Status Word
Accumulators
1 100
2 300
Dec
3 0
4 0
Address Registers
1 0
2 0
Figure 4-4
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Hex
Status Word
8
BR
CC 1
7
6
CC 0
5
OV
4
OS
3
OR
2
STA
1
RLO
/FC
0
Accumulators and Status Word View Object
4-7
Monitoring and Modifying Data with the View Objects
4.5
Monitoring the Block Registers
Displaying the
Contents of the
Block Registers
You can view the contents of the data and logic block registers by opening
the “Block Regs” view object. Select the menu command View Block
Registers to open this view object.
Figure 4-5 shows the “Block Regs” view object.
For more information about the block registers for the S7-300 and S7-400
CPUs, refer to the System Software for S7-300 and S7-400 Program Design
Programming Manual or to the online help for STEP 7.
Block Regs
Data Block
1 0
2 0
Figure 4-5
4-8
Logic Block
1 OB 1
SAC
16
2 0
0
Block Registers View Object
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Monitoring and Modifying Data with the View Objects
4.6
Monitoring the Data in the CPU Stacks
Monitoring the
Nesting Stack and
the MCR Stack
The “Stacks” view object displays the status of both the nesting stack and the
master control relay (MCR) stack. These stacks help you to monitor the state
changes of individual instructions in your program:
S The nesting stack stores up to seven entries. For each entry, the nesting
stack stores the states of the RLO and OR bits of the status word for the
And (A), And Not (AN), Or (O), Or Not (ON), Exclusive Or (X), and
Exclusive Or Not (XN) instructions.
S The MCR stack stores up to eight levels of nesting for an MCR.
To create the view object for viewing the nesting stack and the MCR stack,
use the View " Stacks menu command.
Figure 4-6 shows the “Stacks” view object. Refer to the Statement List (STL)
for S7-300 and S7-400 Programming Manual for more information about the
nesting stack and the MCR stack.
Stacks
Nesting Stack
RLO OR
1
2
3
4
5
6
7
Figure 4-6
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
MCR
MA bit RLO
0
1
2
3
4
5
6
7
Stacks View Object
4-9
Monitoring and Modifying Data with the View Objects
4-10
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
A
Troubleshooting
Table A-1
Troubleshooting
Problem
Your program does not download to the
simulated PLC.
Possible Cause
Verify that the CPU is in either STOP mode or RUN-P mode.
As with a real CPU, you cannot download your program if the simulated
CPU is in RUN mode. Also, you cannot download your program when
the simulated CPU is in Pause mode.
If your program contains an SDB, verify that the CPU is in STOP mode.
As with a real CPU, you can download SDBs only when the simulated
CPU is in STOP mode.
Verify that the CPU and the program use the same node address.
As with a real MPI network, the node address defined for the program
must match the node address of the CPU.
When you download a program and there is no simulated PLC connected
to STEP 7, S7-PLCSIM creates a simulated PLC with the correct node
address for the program; however, if there is already a simulated PLC
connected to STEP 7 and the node address does not match the node
address for the program, STEP 7 displays an error message.
When you attempt to close the simulated If you attempt to close the simulated PLC while one of the STEP 7 tools
PLC, a message alerts you that there is a (such as a variable table) is monitoring the program, STEP 7 alerts you to
connection open.
disconnect the STEP 7 tool from the simulated PLC. Always disconnect
any STEP 7 tool by turning off the monitoring of the program status or
by closing the tool before closing the simulated PLC.
You enter an input value for the
simulated PLC, but this value is
overwritten.
If you want the input value to remain from one scan to the next, use the
peripheral input (PI) memory area instead of the input memory area.
As with a real CPU, the simulated CPU writes the state of the process
image (containing the peripheral input memory) to the input memory
area. Even though there are no input modules in the simulated PLC, the
process image contains “data” (a value of 0) that corresponds to the PI
memory. The input (I) memory area is always overwritten by the PI
memory at the beginning of every scan.
The S7-PLCSIM application does not
First, check to see if Single Scan execution control or the Pause function
respond and appears to have “locked up.” is on. Either one can appear as a lock-up. Turn off Pause, or select
Continuous Scan mode.
If the software does not respond to one of the actions above, press the
Ctrl+Alt+Del keys simultaneously, and end the S7-PLCSIM application.
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
A-1
Troubleshooting
A-2
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
B
S7 Reference Information
Overview
S7-PLCSIM provides view objects for accessing the information stored in the
simulated CPU. You can access any of the memory areas, using the standard
S7/STEP 7 notation for entering the memory addresses.
This appendix provides descriptions of the memory areas, accumulators, and
address registers. It also provides a quick reference for the different formats
for displaying or modifying the data.
Chapter
Overview
Section
Description
Page
B.1
Memory Areas for the S7-300 and S7-400 CPUs
B-2
B.2
S7-PLCSIM Notation for Entering Data
B-4
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
B-1
S7 Reference Information
B.1
Memory Areas for the S7-300 and S7-400 CPUs
Figure B-1 shows the memory areas, accumulators, address registers, and the
status word for the S7-300 and S7-400 CPUs. S7-PLCSIM uses the view
objects to access the values stored in the simulated CPU.
Table B-1 describes the different memory areas.
CPU Accumulators and Registers
Accumulators
32 bits
Memory Areas
Peripheral I/O
PI, PQ
Accumulator 1 (ACCU 1)
Accumulator 2 (ACCU 2)
Accumulator 3 (ACCU 3)
S7-400 only
Accumulator 4 (ACCU 4)
S7-400 only
Address Registers
Outputs
Q
Inputs
I
Bit Memory
M
Timers
T
Counters
C
32 bits
Address Register 1 (AR1)
Executable user program:
Logic blocks
Data blocks
Address Register 2 (AR2)
Data Block Registers
32 bits
DB number for the open DB
DB number for the open instance DB (DI)
Status Word
Status bits
16 bits
Local data for the current block
L
Figure B-1 Memory Areas for the S7-300 and S7-400 CPUs
B-2
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
S7 Reference Information
Table B-1
Memory Areas for the S7-300 and S7-400 CPUs
Name
Input (I)
Memory Area
Process-image
input table
Function of Memory Area
At the beginning of the scan cycle, the operating system reads the inputs
from the process and records the values in this table. The program uses these
values in its normal processing.
For every CPU cycle, Input memory stores the state of the inputs in the
process-image input table. The process-image input table maps the first 512
bytes of the peripheral input memory.
Output (Q)
Process-image
output table
During the scan cycle, the program calculates output values and places them
in this table. At the end of the scan cycle, the operating system reads the
calculated output values from this table and sends them to the process
outputs.
The process-image output table maps the first 512 bytes of the peripheral
output memory.
Bit memory (M)
Memory bits
This area provides storage for interim results calculated in the program. You
designate whether the data are to be accessed as bits, bytes, words, etc.
Peripheral input
(PI)
I/O:
external inputs
Peripheral memory allows direct access to the field devices (physical, or
external, inputs and outputs).
Peripheral output
(PQ)
I/O:
external outputs
Peripheral memory can be accessed in byte, word, and double-word format,
but not as bits.
Timer (T)
Timer
This area provides storage for timer cells. Clock timing accesses the time
cells in this area to update them by decrementing the time value. Timer
instructions access the time cells here.
Counter (C)
Counter
This area provides storage for counters. Counter instructions access them
here.
Data block (DB)
Part of the
program
DBs store the information for the program.
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
B-3
S7 Reference Information
B.2
S7-PLCSIM Notation for Entering Data
The “Variables” view object provides a variety of formats for displaying or
entering the data in your program. The formats allowed are determined by
the size entered with the address: byte (B), word (W), or double word (D).
Table B-2 lists the formats that are available.
Table B-2
Data Formats for the “Variables” View Object
Data Format
B-4
Size
Example
Bits
B
Binary
B and W
10010011
Decimal
B, W, and D
232
Hex (hexadecimal)
B, W, and D
9A
S7 Format
B, W, and D
D#16#09A2FF23
Integer
W and D
623, –2370
BCD (binary-coded decimal)
W and D
400
Real
D
–2134.232323
= off
= on
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Index
A
Accessible nodes
location of button, 3-2
viewing the simulated PLCs, 3-2
Accessing the CPU memory areas, 4-4
Accumulators, 4-7, B-2
Address registers (AR1 and AR2), 4-7, B-2
Addresses, symbolic or absolute, 4-6
Assistance, technical, iv
Authorization, 1-4, 1-7
original disk, 1-5
transfer, 1-5
AUTHORS.EXE, 1-5
B
BCD (binary-coded decimal), format, B-4
Binary data, format, B-4
Bit memory area of memory, description, B-2
Blocks, FBs, FCs, DBs, OBs, 1-3
CPU, continued
resetting the memory (MRES), 4-3
using a variable table, 2-6, 3-6
CPU scan
continuous scan, 3-4
single scan mode, 3-4
Creating view objects, 4-5
Cycling power, 3-4
D
Data block (DB), 4-8
description as area of memory, B-2
Data formats, B-4
Decimal data, format, B-4
Diagnostic information, 1-3
Differences between simulated and real PLCs,
1-3
Disconnecting STEP 7 tools before closing
CPU, 3-6
Downloading a program, 3-3
selecting the simulator, 3-2
C
Changing the CPU operating mode, 4-3
Changing the node address, turning the power
off, 3-4
Closing the simulated PLC, 3-7
Continuous scan, 3-4
Controlling the execution of a program,
simulator options, 3-4
Copy-protection, 1-4
Counters, accessing counter data, 4-4
CPU
areas of memory, B-2
changing operating modes, 4-3
cycling power, 3-4
disconnect STEP 7 tools before closing, 3-6
downloading a program, 3-3
indicators, 4-2
memory areas, 4-4
memory reset (MRES), 4-3
opening a CPU view object, 3-7
operating modes, 4-3
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
E
Entering data, B-4
Errors, during installation, 1-7
Execution control, selecting type of, 3-4
Exiting the application, 3-7
F
Features supported, 1-2, 1-3
H
Halting the program
effect of Pause on STEP 7 tools, 3-6
Pause, 3-4
Hardware requirements, 1-1
Hexadecimal data, format, B-4
Index-1
Index
I
I/O memory supported, 1-3
Input area of memory, description, B-2
Inputs
setting bits, 2-4, 4-5
turning on and off, 4-4
Installation
error, 1-7
overview, 1-1
requirements, 1-1
Installing, PLCSIM, 1-6
Integer, format, B-4
L
L Stack, description of temporary local memory,
B-2
Ladder logic program, monitoring status, 2-7
Layout of view objects, saving, 2-5
LEDs (status indicators), 4-2
Logic blocks supported, 1-3
M
Manuals, STEP 7 set, iii–iv
Master control relay. See MCR stack
MCR stack, 3-5, 4-9
Memory areas, 4-4
Memory bits supported, 1-3
Memory requirements, 1-1
Memory reset (MRES), 4-3
Modes, changing CPU operation, 4-3
Monitoring and modifying data, 4-4
Monitoring and modifying the program
using a variable table, 2-6, 3-6
using view objects, 2-4–2-5, 3-5
MPI address. See Node address
MRES. See Memory reset (MRES)
N
Nesting stack, 3-5, 4-9
Node address
only one PLC at a time, 3-7
turning the power off before changing, 3-4
O
Opening a layout, 2-5
Opening a PLC, 3-7
Index-2
Operating modes, changing CPU, 4-3
Operating system requirements, 1-1
Options, simulation, 3-4
Organization blocks (OBs) supported, 1-3
Output area of memory, description, B-2
Outputs, accessing Q and PQ memory, 4-4
Overview
installation, 1-1
product features, 1-2
P
Pause function, 3-4
with STEP 7 tools, 3-6
Peripheral input and output areas of memory
accessing, 4-4
description, B-2
PLC
closing, 3-7
opening, 3-7
saving configuration, 3-7
PLCSIM
errors during installation, 1-7
Installation, 1-6
Power on/off
CPU indicator, 4-2
cycling power, 3-4
Product overview, 1-2
Program editor
downloading a program, 3-3
monitoring status, 2-7
R
Real number, format, B-4
Requirements, for installing PLCSIM, 1-1
Resetting the CPU memory, 4-3
Resetting timers, 2-5
RUN mode
changing the CPU mode to, 4-2
CPU indicator, 4-2
Running a program, 2-4–2-5
RUN-P mode, changing the CPU mode to, 4-2
S
S7 format, B-4
Sample program, running, 2-4–2-5
Saving
a layout of view objects, 2-5
the PLC configuration, 3-7
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Index
Scan modes, 3-4
Showing symbol names, 4-6
SIMATIC Manager
downloading a program, 3-3
selecting the simulator, 3-2
Simulation session, turning on and off, 3-2
Simulator button, SIMATIC Manager, 3-2
Simulator options
continuous scan, 3-4
Pause, 3-4
single scan mode, 3-4
Single scan mode, 3-4
Stacks, 3-5, 4-9
Starting the program, 2-4
Status indicators (LEDs), 4-2
Status word, 4-7
STEP 7 manuals, iii–iv
STEP 7 tools
disconnect before closing CPU, 3-6
monitoring logic execution, 2-7
variable table (VAT), 2-6, 3-6
STOP mode
changing the CPU mode to, 4-2
CPU indicator, 4-2
Stop mode, before resetting CPU memory
(MRES), 4-3
Symbol names for addresses, 4-6
System fault (SF), CPU indicator, 4-2
System functions (SFCs) supported, 1-3
Timers
accessing timer data, 4-4
creating, 2-3
execution times, 1-3
resetting, 2-5
Toolbar buttons
in PLCSIM window, 2-4, 3-4, 3-5
in SIMATIC Manager, 2-2, 3-2
U
Uninstalling, PLCSIM, 1-6
Using STEP 7 tools, 2-6–2-7
V
Variable table, monitoring and modifying the
program, 2-6, 3-6
Variables, modifying data, 4-5
Variables view object, data formats, B-4
VAT. See Variable table
View object
accessing data in memory, 4-4–4-5
accumulators, 3-5
block registers, 3-5
CPU, 3-7, 4-2
saving the PLC, 3-7
stacks, 3-5, 4-9
variable, 3-5
T
Technical assistance, iv
Timer area of memory, description, B-2
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
W
Windows 95 operating system, 1-1
Index-3
Index
Index-4
PLC Simulation for S7-300 and S7-400
C79000-G7076-C201-01
Siemens AG
AUT E 146
Östliche Rheinbrückenstr. 50
D–76181 Karlsruhe
Federal Republic of Germany
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PLC Simulation for S7-300 and S7-400
6ES7841-0AA00-8BA0-01
1
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PLC Simulation for S7-300 and S7-400
6ES7841-0AA00-8BA0-01
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